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A TIRF Microscopy Technique for Real-time, Simultaneous Imaging of the TCR and its Associated Signaling Proteins
16:10

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Published on: March 22, 2012

The B-cell antigen receptor signals through a preformed transducer module of SLP65 and CIN85

Thomas Oellerich1, Vanessa Bremes, Konstantin Neumann

  • 1Institute of Cellular and Molecular Immunology, Georg-August-University Göttingen, Germany.

The EMBO Journal
|August 9, 2011
PubMed

Insights

The B-cell antigen receptor (BCR) signaling relies on spleen tyrosine kinase (Syk) and SLP65. A constant SLP65/CIN85 complex is crucial for BCR signal initiation and B-cell activation.

Area of Science:

  • Immunology
  • Cell Signaling
  • Molecular Biology

Background:

  • Spleen tyrosine kinase (Syk) and SLP65 (also known as BLNK) are key proximal signal transducers for the B-cell antigen receptor (BCR).
  • Limited understanding of BCR signal initiation and processing exists due to incomplete knowledge of SLP65 interactors and their kinetics.

Purpose of the Study:

  • To determine and quantify the in vivo interactomes of SLP65 in resting and stimulated B cells.
  • To elucidate the role of SLP65 interactions in BCR signal transduction.

Main Methods:

  • Mass spectrometry-based in vivo interactome analysis of SLP65.
  • Co-immunoprecipitation experiments.
  • Live cell imaging.

Main Results:

  • SLP65 orchestrates a dynamic signaling network of approximately 30 proteins.
  • A constitutive SLP65/CIN85 complex is essential for SLP65 phosphorylation and plasma membrane translocation.
  • The SLP65/CIN85 complex is required for BCR-induced Ca(2+) and NF-κB responses.
  • Both SLP65 and CIN85 are critical components of the BCR primary transducer module.

Conclusions:

  • The SLP65/CIN85 interaction is a pivotal, stimulation-independent event for initiating BCR signaling.
  • SLP65 and CIN85 form a core module essential for both the initiation and progression of BCR signal transduction.

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